or "Alte Tonarten" of the 16th and 17th centuries found by Bernhard Meier.

The word encompasses several additional meanings. Authors from the 9th century until the early 18th century (e.g., Guido of Arezzo) sometimes employed the Latin modus for interval, or for qualities of individual notes. In the theory of late-medieval mensural polyphony (e.g., Franco of Cologne),